arXiv subjects

Marc T. Cuairan

Publications and source records attributed to Marc T. Cuairan.

6 recordsLinked to original sources

arXiv2023

Vacuum levitation and motion control on chip

Levitation in vacuum has evolved into a versatile technique which has already benefited diverse scientific directions, from force sensing and thermodynamics to material science and chemistry. It also holds great promises of advancing the study of quantum mechanics in the unexplored macroscopic regime. While most current levitation platforms are complex and bulky, miniaturization is sought to gain robustness and facilitate their integration into confined settings, such as cryostats or portable devices. Integration on chip is also anticipated to enhance the control over the particle motion through a more precise engineering of optical and electric fields. As a substantial milestone towards this goal, we present here levitation and motion control in high vacuum of a silica nanoparticle at the surface of a hybrid optical-electrostatic chip. By combining fiber-based optical trapping and sensitive position detection with cold damping through planar electrodes, we cool the particle motion to a few hundred phonons. Our results pave the way to the next generation of integrated levitation platforms combining integrated photonics and nanophotonics with engineered electric potentials, towards complex state preparation and read out.

physics.optics↗

arXiv2022

A chemical nano-reactor based on a levitated nanoparticle in vacuum

A single levitated nanoparticle is used as a nano-reactor for studying surface chemistry at the nanoscale. Optical levitation under controlled pressure, surrounding gas composition, and humidity provides extreme control over the nanoparticle, including dynamics, charge, and surface chemistry. Using a single nanoparticle avoids ensemble averages and allows to study how the presence of silanol groups at its surface affects the adsorption and desorption of water from the background gas with unprecedented real time, spatial, and temporal resolution. Here, we demonstrate the unique potential of this versatile platform by studying the Zhuravlev model in silica particles. In contrast to standard methods, our system allowed the first observation of an abrupt and irreversible change in scattering cross section, mass, and mechanical eigenfrequency during the dehydroxylation process, indicating changes in density, refractive index and volume.

physics.chem-ph↗

arXiv2021

Precision calibration of the Duffing oscillator with phase control

The Duffing oscillator is a nonlinear extension of the ubiquitous harmonic oscillator and as such plays an outstanding role in science and technology. Experimentally, the system parameters are determined by a measurement of its response to an external excitation. When changing the amplitude or frequency of the external excitation, a sudden jump in the response function reveals the nonlinear dynamics prominently. However, this bistability leaves part of the full response function unobserved, which limits the precise measurement of the system parameters. Here, we exploit the often unknown fact that the response of a Duffing oscillator with nonlinear damping is a unique function of its phase. By actively stabilizing the oscillator's phase we map out the full response function. This phase control allows us to precisely determine the system parameters. Our results are particularly important for characterizing nanoscale resonators, where nonlinear effects are observed readily and which hold great promise for next generation of ultrasensitive force and mass measurements. We demonstrate our approach experimentally with an optically levitated particle in high vacuum.

physics.app-ph↗

arXiv2019

Narrowband photon pairs with independent frequency tuning for quantum light-matter interactions

We describe a cavity-enhanced spontaneous parametric down-conversion (CE-SPDC) source for narrowband photon pairs with filters such that over 97% of the correlated photons are in a single mode of 4.3(4) MHz bandwidth. Type-II phase matching, a tuneable-birefringence resonator, MHz-resolution pump tuning, and tuneable Fabry-Perot filters are used to achieve independent signal and idler tuning. We map the CE-SPDC spectrum using difference frequency generation to precisely locate the emission clusters, and demonstrate CE-SPDC driven atomic spectroscopy. The generated photon pairs efficiently interact with neutral rubidium, a well-developed system for quantum networking and quantum simulation. The techniques are readily extensible to other material systems.

quant-ph↗

arXiv2019

Optimal Feedback Cooling of a Charged Levitated Nanoparticle with Adaptive Control

We use an optimal control protocol to cool one mode of the center of mass motion of an optically levitated nanoparticle. The feedback technique relies on exerting a Coulomb force on a charged particle with a pair of electrodes and follows the control law of a linear quadratic regulator, whose gains are optimized by a machine learning algorithm in under 5 s. With a simpler and more robust setup than optical feedback schemes, we achieve a minimum center of mass temperature of 5 mK at $3\times 10^{-7}$ mbar and transients 10 to 600 times faster than cold damping. This cooling technique can be easily extended to 3D cooling and is particularly relevant for studies demanding high repetition rates and force sensing experiments with levitated objects.

physics.ins-det↗

arXiv2019

Accurate mass measurement of a levitated nanomechanical resonator for precision force sensing

Nanomechanical resonators are widely operated as force and mass sensors with sensitivities in the zepto-Newton and yocto-gram regime, respectively. Their accuracy, however, is usually undermined by high uncertainties in the effective mass of the system, whose estimation is a non-trivial task. This critical issue can be addressed in levitodynamics, where the nanoresonator typically consists of a single silica nanoparticle of well-defined mass. Yet, current methods assess the mass of the levitated nanoparticles with uncertainties up to a few tens of percent, therefore preventing to achieve unprecedented sensing performances. Here, we present a novel measurement protocol that uses the electrical field from a surrounding plate capacitor to directly drive a charged optically levitated particle in moderate vacuum. The developed technique estimates the mass within a statistical error below 1% and a systematic error of 2%, and paves the way toward more reliable sensing and metrology applications of levitodynamics systems.

physics.ins-det↗